<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>计算器</title>
    <style>
        body {
            font-family: Arial, sans-serif;
            background-color: #f0f0f0;
            margin: 0;
            padding: 0;
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
        }

        .container {
            background-color: #fff;
            padding: 25px;
            border-radius: 10px;
            box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
            width: 350px;
            text-align: center;
        }

        h1 {
            color: #333;
            margin-bottom: 20px;
        }

        .input-group {
            margin-bottom: 15px;
            display: flex;
            flex-direction: column;
            align-items: flex-start;
        }

        .input-group label {
            font-size: 14px;
            color: #666;
            margin-bottom: 5px;
        }

        .input-group input {
            width: 95%;
            padding: 10px;
            border: 1px solid #ccc;
            border-radius: 5px;
            font-size: 16px;
        }

        .button-group {
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
        }

        .button-group input {
            padding: 10px 20px;
            margin: 5px;
            border: none;
            border-radius: 5px;
            font-size: 16px;
            cursor: pointer;
            background-color: #007BFF;
            color: #fff;
            transition: background-color 0.3s;
        }

        .button-group input:hover {
            background-color: #0056b3;
        }

        .button-group input:active {
            transform: scale(0.98);
        }
    </style>
</head>
<body>
<div class="container">
    <form action="" method="post">
        <h1>计算器</h1>
        <div class="input-group">
            <label for="num1">数字1:</label>
            <input type="text" name="num1" id="num1" required>
        </div>
        <div class="input-group">
            <label for="num2">数字2:</label>
            <input type="text" name="num2" id="num2" required>
        </div>
        <div class="button-group">
            <input type="submit" value="点击相加" formaction="calc/sum">
            <input type="submit" value="点击相减" formaction="calc/subtract">
            <input type="submit" value="点击相乘" formaction="calc/multiply">
            <input type="submit" value="点击相除" formaction="calc/division">
        </div>
    </form>
</div>
</body>
</html>